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1 California Department of Water Resources 2 Water Use and Efficiency Branch 3 4 Discussion Paper: Proposed Regulation on 5 Range of Options for Agricultural Water 6 Measurement 7 June 13, 2011 8 9

10SB X7-7, enacted in November of 2009, includes provisions on water conservation, 11measurement, and reporting activities for agricultural water suppliers. DWR has coordinated 12with the Agricultural Water Management Council and an Agricultural Stakeholder Committee 13(ASC) to develop a regulation for a range of agricultural water measurement options that water 14suppliers may use to measure water delivered to customers.

15 1.0 Provisions Related to Agricultural Water 16 Measurement

17Paragraph 10608.48(i)(1) of SB X7-7 states:

18 The department shall adopt regulations that provide for a range of 19 options that agricultural water suppliers may use or implement to 20 comply with the measurement requirement in paragraph (1) of 21 subdivision (b). 22That paragraph refers to 10608.48(b) of SB X7-7:

23 Agricultural water suppliers shall implement all of the following critical 24 efficient management practices: 25 (1) Measure the volume of water delivered to customers with sufficient 26 accuracy to comply with subdivision (a) of Section 531.10 and to 27 implement paragraph (2).

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1 (2) Adopt a pricing structure for water customers based at least in part 2 on quantity delivered. 3Section 10813 defines customer as “a purchaser of water from a water supplier who uses water for 4agricultural purposes.” Note however, that Section 10813 provides definitions for Part 2.8, 5Agricultural Water Management Planning, but not specifically for Part 2.55 of SB X7-7 which 6includes the paragraphs on water measurement. Therefore, DWR has developed a more 7specific definition of customer for use in the measurement regulation (see Attachment 1).

8Section 531.10(a) of the California Water Code (CWC), referred to above, requires 9that: 10 (a) An agricultural water supplier shall submit an annual report to the 11 department that summarizes aggregated farm-gate delivery data, on a 12 monthly or bi-monthly basis, using best professional practices. 13Note also that CWC §531 defines a lower size threshold for aggregate reporting 14purposes than SB X7-7 specifies for its measurement regulations. 15Section 10608.12 (a) of SB X7-7 states: 16 “Agricultural water supplier” means a water supplier, either publicly or 17 privately owned, providing water to 10,000 or more irrigated acres, 18 excluding recycled water. “Agricultural water supplier” includes a 19 supplier or contractor for water, regardless of the basis of right, that 20 distributes or sells water for ultimate resale to customers. “Agricultural 21 water supplier” does not include the department. 22Further, agricultural water suppliers that provide water to less than 25,000 acres 23only need to comply if funding is provided to cover additional costs imposed 24(see Section 10853). 25In contrast, CWC §531(b) states: 26 "Agricultural water supplier" means a supplier either publicly or 27 privately owned, supplying 2,000 acre-feet or more of surface water 28 annually for agricultural purposes or serving 2,000 or more acres of 29 agricultural land. An agricultural water supplier includes supplier or 30 contractor for water, regardless of the basis of right, which distributes or 31 sells water for ultimate resale to customers.

32 2.0 Timeline for Agricultural Water Suppliers to 33 Comply with Measurement Requirements

34DWR is authorized to issue an emergency regulation to provide for a range of measurement 35options, followed by a permanent regulation. DWR considered issuing an emergency 36regulation by January, 2011, but discussion with the ASC indicated that it needed more time to 37develop and evaluate terms of the regulation. Instead, DWR has chosen to develop and submit

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1both an emergency and a permanent regulation in spring of 2011 to allow time for agricultural 2water suppliers to plan and implement the water measurement requirements of SB X7-7. 3Several sections of SB X7-7 determine the date by which agricultural water suppliers must 4comply with the measurement requirements. These are:

5  Subdivision 10608.48(a) of SB X7-7 sets July 31, 2012 as the date by which agricultural 6 water suppliers shall implement efficient water management practices that include 7 measuring the volume of water delivered to customers.

8  Notwithstanding the July 31, 2012 date stated in 10608.48(a), SB X7-7 subdivision 9 10608.56 (b) establishes the onset of the grant and loan eligibility test to be July 1, 2013:

10 On and after July 1, 2013, an agricultural water supplier is not eligible 11 for a water grant or loan awarded or administered by the state unless the 12 supplier complies with this part. 13  An agricultural water supplier will still be eligible for grants and loans if the supplier 14 has submitted to DWR for approval a schedule, financing plan, and budget, to be 15 included in the grant or loan agreement, for implementation of the efficient water 16 management practices (paragraph 10608.56 (d)).

17To allow time for planning, financing, and implementation of water measurement programs to 18comply with the SB X7-7 requirement, DWR and the ASC also considered a flexible phasing of 19implementation of the regulation, with full compliance achieved by the year 2020. Under this 20approach, agricultural water suppliers would be required to report existing water measurement 21and include in their 2012 Water Management Plans a plan to achieve compliance by 2020, 22perhaps with interim goals to be met by 2015. Many ASC members representing diverse 23interests supported this approach in concept. DWR staff determined that the proposed 24regulation could not change the formal target date of compliance to 2020. Therefore, the 25proposed regulation provides that suppliers will be compliant by demonstrating that all 26measurement devices meet the standard by July 31, 2012 or by including in their 2012 AWMP a 27plan and schedule for bringing all existing devices up to the applicable numerical standard (see 28also Section 5.2.4 below).

29 3.0 Applicability

30Only agricultural water suppliers that provide water to more than 10,000 irrigated acres are 31subject to the water measurement regulations (section 10608 (a)). Further, agricultural water 32suppliers that provide water to more than 10,000 irrigated acres but less than 25,000 acres only 33must comply with water measurement requirements if sufficient funding is provided 34specifically for that purpose (section 10853).

35Both of these acreage thresholds exclude acreage served by recycled water. For purposes of the 36measurement requirements, DWR staff has clarified that this exclusion applies to lands that are 37irrigated only using recycled water. Recycled water means municipal or industrial wastewater 38that has been treated for waste and is thus usable for irrigation (CWC §13050 (n))). It does not 39mean untreated return flow from other irrigated lands.

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1It is important to distinguish between the acreage thresholds for reporting purposes under 2CWC §531, and the acreage thresholds for the measurement requirements defined in 3Section 10608 of SB X7-7. All agricultural water suppliers “supplying 2,000 acre-feet or more of 4surface water annually for agricultural purposes or serving 2,000 or more acres of agricultural 5land” must meet the reporting requirements of CWC §531.10(a). The following summarizes 6how the Section 10608 (a) water measurement requirements will apply to agricultural water 7suppliers depending on the size of the agricultural water supplier’s irrigated area.

8  Agricultural water suppliers providing water to less than 10,000 irrigated acres, 9 excluding acres that receive only recycled water, are not subject to the water 10 measurement requirements. They remain subject to measurement requirements of 11 Section 531 of the Water Code if they deliver more than 2000 acre feet of water or irrigate 12 2000 or more acres of land.

13  Agricultural water suppliers providing water to 10,000 or more irrigated acres but less 14 than 25,000 irrigated acres, excluding acres that receive only recycled water, are not 15 required to implement the water measurement requirements unless sufficient funding is 16 provided specifically for that purpose.

17  Agricultural water suppliers providing water to 25,000 irrigated acres or more, 18 excluding acres that receive only recycled water, shall measure water deliveries 19 consistent with the water measurement requirements.

20Any agricultural water supplier that meets the water measurement requirements developed 21under paragraph 10608.48(i)(1) of SB X7-7, and submits an annual report to the Department that 22summarizes aggregated farm-gate delivery data on a monthly or bi-monthly basis, will also be 23deemed to comply with the reporting and measurement requirements of CWC §531.10.

24For purposes of the regulation, irrigated acres are calculated as the average of the previous five 25years of acreage within the agricultural water supplier’s service area that has received irrigation 26water from the agricultural water supplier. It includes private lands that are irrigated and used 27for managed wildlife habitat, but excludes state or federally managed wildlife refuges. The 28measurement of irrigated acreage within a particular field has not been specified in the 29proposed regulation. Therefore, water suppliers may report either gross or net irrigated 30acreage. Net acreage of a field includes only the land area receiving irrigation water. It 31excludes portions of a field used for farm roads, equipment, ditches, etc. For example, a field 32that measures a total of 80 acres may only have 70-75 acres actually receiving irrigation water. 33Water suppliers and water users typically use net acreage for purposes of calculating aggregate 34irrigated acreage and water use.

35Paragraph 10608.8 (d) also excludes from the measurement requirement any agricultural water 36supplier “that is a party to the Quantification Settlement Agreement, as defined in subdivision 37(a) of Section 1 of Chapter 617 of the Statutes of 2002, during the period within which the 38Quantification Settlement Agreement remains in effect.” Imperial Irrigation District (IID), 39Coachella Valley Water District (CVWD), and Metropolitan Water District of Southern 40California (MWD) were the water suppliers that signed the original QSA. In addition

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1San Diego County Water Agency (SDCWA) is listed as a party to the QSA in Chapter 617 of the 2Statutes of 2002. The Quantification Settlement Agreement is now usually viewed by the 3parties as a package of agreements. The proposed regulation does not specify which agencies 4may fall under this exclusion. For purposes of cost and fiscal impact assessment, the four 5suppliers listed above (IID, MWD, SDCWA, and CVWD) are assumed to fall under the 6exclusion. 7 83.1 Applicability to Wholesale Suppliers 9Wholesale water suppliers include entities responsible for conveyance and delivery of 10agricultural water to one or more other water suppliers (the receiving water suppliers). 11Wholesale suppliers are subject to the measurement regulation provided that they meet the size 12thresholds described above. DWR is specifically excluded from the definition of an agricultural 13water supplier. Federal agencies, such as the U.S. Bureau of Reclamation, are also excluded, 14based on an assumption that the State cannot mandate that a federal agency take action or 15spend money that Congress has not directed. Canal authorities or other entities that convey or 16deliver water through facilities owned by a federal agency were considered but excluded. DWR 17staff determined that, because the facilities are owned by, in these cases, the U.S. Bureau of 18Reclamation, they would also fall under the federal exclusion. Staff noted that such entities 19already measure and report diversions and deliveries.

20A wholesale supplier or other, non-retail entity subject to the water measurement requirements 21must measure deliveries to its customers only. It is not required to measure deliveries that its 22retail customers make to their customers. For example, if a wholesale supplier delivers water 23only to ten retail agricultural water suppliers, and those retail suppliers serve a total of more 24than 25,000 irrigated acres, the wholesale supplier must measure deliveries to each of the ten 25retail suppliers, but not to the individual customers served by each of the ten retail suppliers. If 26the wholesale supplier also delivers water to final agricultural customers, it must also measure 27deliveries to each of those customers.

28To determine whether it meets acreage thresholds for compliance, the wholesale water supplier 29or other entity must include all customers’ irrigated acres that fall within the service boundary 30of the wholesale supplier. 313.2 Applicability to CVP and Other Reclamation Contractors 32Sections 10608.48 (f) and 10848 of SB X7-7 state that water conservation or water management 33plans submitted to and accepted by the U.S. Bureau of Reclamation shall be deemed to meet the 34water management plan requirements under SB X7-7. Staff considered whether this implied 35that CVP contractors that meet Reclamation’s water delivery measurement standards would be 36deemed in compliance with the proposed measurement regulation. Reclamation’s 2008 37Conservation and Efficiency Criteria are developed for CVP contractors to comply with the 38Central Valley Project Improvement Act (CVPIA) section 3405(e). The Criteria include a 39measurement accuracy standard that requires contractors to “measure the volume of water 40delivered by the contractor to each customer… with devices that are operated and maintained 41to a reasonable degree of accuracy, under most conditions, to +/- 6 percent by volume.”

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1 2In addition, other USBR contractors who are subject to the Reclamation Reform Act (RRA), but 3not CVPIA, may have submitted water management plans to Reclamation that meet the same 4water measurement standard. Staff considered several options for CVP and other Reclamation 5contractors: 1) include no reference in the proposed regulation to any Reclamation water 6measurement standard or requirements; 2) allow Reclamation contractors an alternative 7compliance path if they submit a water management plan demonstrating that all water 8delivered by the contractor is delivered through measurement devices that meet the 9measurement accuracy standards specified in Reclamation’s Conservation and Efficiency 10Criteria of 2008 or future amendments; or 3) allow the alternative compliance so long as 11Reclamation’s numerical accuracy standard meets or exceeds the State’s standard.

12After extensive discussion among DWR staff, USBR staff, and ASC members, the proposed 13regulation uses the second approach. This provides USBR contractors an alternative 14compliance path; references a specific, dated document (or revisions adopted by Reclamation 15specific to that document); and does not place a perceived constraint on the federal agency’s 16latitude to amend future versions of its guidelines.

17 4.0 Requirements and Criteria

18The following requirements and criteria apply to the agricultural water suppliers.

19  Suppliers must measure water delivered to customers. The measurement must be 20 accurate enough to allow the water supplier to charge its customers at least in part based 21 on volume of water delivered (section 10608.48(b)(1));

22  Measurement in 10608.48(i)(1) refers only to water delivered under the control of the 23 water supplier. For example, water delivered by the retail supplier to a customer at a 24 turnout is subject to the measurement requirements; however, the customer may route 25 that delivery to one or more fields on the customer’s farm, and delivery to each of those 26 fields would not be subject to the measurement requirements. Similarly, a wholesale 27 supplier must measure the delivery to its customers. The wholesale supplier is not 28 responsible for measuring water delivered to each of the retail supplier’s customers.

29  A customer is defined in the proposed regulation as a “purchaser of water from an 30 agricultural water supplier who has a contractual arrangement with the agricultural water 31 supplier for the service of conveying water to the customer delivery point.”

32  In most cases a water supplier’s customers would correspond to its billing accounts. 33 Nevertheless, measurement must occur at discrete physical locations, so if a supplier 34 delivers water to one customer at more than one location, the measurement 35 requirements apply at each of those delivery locations.

36  Measurement in 10608.48(i)(1) refers only to water delivered to customers by an 37 agricultural water supplier. It does not include groundwater pumped from private 38 wells even though the groundwater may be managed by a public agency. Groundwater

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1 pumped by wells owned by the agricultural water supplier and provided to customers 2 as part of its delivered irrigation water is subject to the requirements. DWR staff and the 3 ASC considered whether water that a supplier uses to recharge groundwater should be 4 considered as delivered water covered by the measurement accuracy standards. Staff 5 concluded that water used for groundwater recharge need not be subject to the 6 standard. Most agricultural water suppliers subject to the regulation have no control 7 over the private wells that make use of the recharged water. Those that do have such 8 control also have an incentive to measure recharged water. In addition, water is 9 recharged under a wide range of circumstances, including the opportunistic diversion of 10 flood flows. It may not be possible to measure accurately the volume diverted and 11 recharged in some situations.

12  Irrigation return flow leaving fields, farms, or water supplier boundaries is not subject to 13 the measurement requirements, except if it is collected by the water supplier and 14 provided as irrigation delivery to other customers. 15 16

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1 5.0 Frameworks Considered for Creating a 2 Range of Water Measurement Options

3DWR is required by Section 10608.48(i)(1) to develop and adopt a regulation that provides for a 4range of measurement options. These options allow for a range of conditions and delivery 5system configurations, including pressurized pipe delivery, non-pressurized pipe delivery, and 6open-channel delivery. 75.1 Frameworks Considered for Creating a Range of Water 8 Measurement Options 9DWR staff, with input from the Agricultural Stakeholder Committee and the A2 Subcommittee, 10considered three alternative frameworks for developing a range of options for measuring 11agricultural water deliveries:

12 (1) List of acceptable devices: DWR would develop a regulation that includes a list of 13 acceptable measurement devices maintained in defined manners to achieve desired 14 accuracy. Suppliers could choose among those devices based on their local 15 conditions.

16 (2) Statewide performance standard for device accuracy: DWR would develop a 17 regulation setting a performance standard that defines minimum benchmarks for 18 device accuracy that could be met or bettered by a range of devices. Suppliers could 19 measure delivery using greater accuracy than the standard, based on their and their 20 customers’ demands. Included under this option would be requirements defining 21 standards for device rating or calibration but could also set minimum standards for 22 administration, monitoring and maintenance protocols for devices.

23 (3) Locally-determined standards for device accuracy: DWR would develop a 24 regulation that provides a process for suppliers to assess and report their 25 measurement accuracy. For example, the regulation could specify a set of 26 information that a supplier would report to DWR documenting 1) the procedures by 27 which it determined sufficient accuracy, and 2) information documenting its 28 measurement devices and accuracies. The information must demonstrate that the 29 supplier’s measurement accuracy is sufficient to meet the two purposes stated in 30 SB X7-7: submit an annual report to the department that summarizes aggregated 31 farm-gate delivery data, and adopt a pricing structure based in part on the volume 32 delivered.

33In evaluating these frameworks, DWR staff considered the following criteria:

34  Section 10608.48(b) directs a qualifying agricultural water supplier to measure with sufficient 35 accuracy to (1) enable its adoption of a pricing structure based in part on the volume delivered to 36 customers, and (2) allow it to report to DWR a summary of aggregated farm-gate deliveries 37 [CWC §531.10(a)]. This latter objective is tied to the stated intent in Section 1 of Assembly Bill

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1 1404 that “[a]ppropriate measurement of water use facilitates better water management by 2 making information available to local, state, and federal water managers and planners.” 1

3  The need for a certain degree of confidence – through use of a minimum benchmark - that data 4 submitted to DWR [under CWC §531.10(a)] closely represents actual deliveries.

5  The need to provide a reasonable degree of flexibility to agricultural water suppliers to 6 accommodate a wide range of water delivery circumstances and supplier/customer relationships.

7  The recognition that an agricultural water supplier and its customer have a business relationship 8 associated with the delivery of water and the payment for such services. This relationship in 9 itself can provide incentives necessary to measure accurately.

10  The need to balance theoretically potential accuracy with economically and technically practical 11 accuracy while meeting the objectives of the statute.

12  The recognition that the term “sufficient accuracy” in the statute refers to the measurement of a 13 volume of water delivered to customers, which would be stated as a numeric value. Measuring 14 and determining a numeric value would imply a numeric standard.

15  The recognition that the delivery of water by most agricultural water suppliers is not equivalent 16 to the sale of a commodity, which would be more responsive to market forces. Thus, the 17 relationship between an agricultural water supplier and its customer and the need for accuracy 18 may not be driven primarily by incentives associated with the cost of water and its delivery.

19Based on these considerations, DWR staff proposed that the second framework – specifying a 20performance standard that defines minimum device accuracy benchmarks – provided the most 21appropriate framework to establish a range of measurement options. A performance standard 22meets the intent of the legislation in the most flexible and cost-effective manner.

23Staff did not recommend adopting a list of acceptable measurement devices for the following 24reasons:

25  Dictating specific devices can unintentionally constrain suppliers or impose unreasonable or 26 unnecessary costs to accommodate the defined devices.

27  Measurement technology changes over time, so a list of approved devices would need frequent 28 review and modification.

29  Measurement requirements are to assure agricultural water suppliers are able to meet 30 10608.48(b), which states “Measure the volume of water delivered to customers with sufficient 31 accuracy…” The paragraph is stated in terms of measurement accuracy, not specific devices or 32 technologies.

33Staff compiled a list of devices and associated measurement accuracies, and these are 34summarized in Attachment 3. Water suppliers are not required to select a device from this list. 35Rather, the purpose of the list is to assure that there exists a reasonably wide range of devices

21 AB 1404 was approved by the Governor on October 14, 2007. Section 1 includes several legislative findings and declarations that 3demonstrate the intent of the statutes enacted by the bill.

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1capable of meeting the adopted accuracy standard. Water suppliers can use a device on this list 2or any other current or future device that meets the standard.

3Staff considered the request by several water suppliers that the regulation allow local conditions 4to determine appropriate measurement accuracy. The rationale suggested was that, once all 5suppliers adopt a pricing structure for water customers based at least in part on quantity 6delivered, per Section 10608.48(b)(2), all will have adequate incentive to measure accurately as 7needed to serve that and other local purposes. DWR staff did not recommend this for the 8following reasons:

9  Volumetric pricing is only one of the purposes of sufficient accuracy. The accuracy must also be 10 sufficient from the State’s viewpoint to provide reliable reporting of aggregate farm-gate delivery 11 data. For example, a supplier could set a volumetric price that is so low that both the supplier 12 and its customers would accept measurement accuracy that the State would deem insufficient for 13 aggregate reporting purposes.

14  This framework is essentially the status quo - suppliers already measure water according to local 15 conditions, cost-effectiveness, the suppliers’ accounting needs, and customer demands. 16 Nevertheless, SB X7-7 specifically directs DWR to adopt a regulation.

17Attachment 2 provides examples of similar performance standards developed by USBR and 18other western states. It is worth noting that, of the six states surveyed for a CALFED (2003) 19report on appropriate agricultural water measurement (Arizona, Colorado, Idaho, Kansas, 20Oregon, and Washington) only one, Arizona, had numerical accuracy standards for points of 21irrigation water delivery by suppliers to individual customers. None of those states surveyed 22required specific hardware devices (though some included examples of devices that would 23comply). 245.2 Range of Water Measurement Options 25Using the framework described above, DWR staff developed a range of options that that water 26suppliers may use or implement to comply with the measurement requirement. Water 27suppliers subject to the requirement shall use one of the following options to measure water 28delivered to customers (for exact language of the options, see the proposed regulation):

29  The first option applies to measurement at the location of delivery to individual 30 customers.

31  The second option applies to measurement upstream of the delivery points to multiple 32 customers. Under certain circumstances and with justification acceptable to DWR, this 33 option allows the supplier to measure water at a point on the delivery system lateral, 34 upstream of delivery to more than one customer.

35Within the two options, the proposed regulation provides additional flexibility to demonstrate 36compliance. For newly-installed devices, the supplier may use a laboratory certification or a 37defined non-laboratory certification procedure. For existing measurement devices, the supplier 38may use in-field testing, field inspection and analysis, or certification of design and installation.

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15.2.1 Rationale for proposed options 2The options attempt to provide flexibility for agricultural water suppliers to measure water 3with sufficient accuracy to meet the two purposes stated in the legislation: to submit an annual 4report of aggregated farm-gate delivery and to adopt a pricing structure for water customers 5based at least in part on quantity delivered. The options also encompass existing measurement 6devices and newly-installed devices. The specific numerical accuracy standards are proposed 7based on the following considerations:

8  DWR staff, with the assistance of ASC members, compiled information on the accuracy 9 capabilities of different types of measurement devices. The purpose of the compilation 10 was to determine that the proposed measurement options and their associated 11 numerical standards provided suppliers with a range of feasible hardware options. 12 This information is summarized in Attachment 3.

13  Suppliers that rely on a laboratory certification must meet a higher accuracy standard 14 than those using a non-laboratory (in-field or as-installed) standard. This accounts for 15 the additional uncertainties and ranges of conditions encountered under installed field 16 conditions.

17  Suppliers that choose to measure upstream of the point of delivery to individual 18 customers must meet some additional requirements in order to justify this approach. 19 Aggregate measurements must be apportioned to individual customers, a process that 20 introduces additional error into the calculation of final volume delivered. Staff 21 considered requiring that the measurement device itself be able to achieve sufficient 22 accuracy to offset the potential error in apportioning water delivered to individual 23 customers. However, this introduced additional complexity into the regulation. 24 Therefore, the proposed regulation uses the same numerical standards for any point of 25 measurement. 265.2.2 Evaluating accuracy of existing devices 27In order to demonstrate compliance with the defined standard for existing devices, DWR staff 28and the ASC considered options that would address two objectives: (1) provide DWR with 29reasonable evidence that existing devices declared to be in compliance were actually in 30compliance, and (2) give agricultural water suppliers some flexibility in methods to provide 31such evidence. Two options were developed to provide such flexibility.

32 Field testing. This method entails the physical evaluation of the accuracy of a device’s 33 measured values by using another device known to be more accurate. For instance, the 34 determination of flow rate believed to be measured by a constant head orifice gate would be 35 checked through the use of a current meter or other appropriate device designed and 36 intended for such evaluations for a specified period of time. In-field tests are expensive and 37 time-consuming to conduct, so DWR staff and the ASC determined that testing a 38 representative sample of like-devices would be appropriate. 39 40 DWR staff considered several approaches to determining the appropriate sampling design

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1 and sample size. One approach was simply to include a general requirement that suppliers 2 use sound statistical sampling procedures to select and test a representative sample. A 3 second approach was to include some rules for determining the sample size, such as a fixed 4 percent of the total number of devices with perhaps a minimum and maximum number to 5 be tested. The third approach considered would specify the formula or statistical rules that 6 must be used to determine sample size.

7 DWR staff found no comparable examples of other states that had detailed statistical 8 sampling requirements for in-field testing of the measurement accuracy of agricultural 9 water delivery. Formulas for calculating sample size depend on the existing variability in 10 accuracy of the devices being sampled and on the target level of confidence and width of 11 error interval for the resulting estimates. DWR staff developed some example formulas and 12 target confidence levels, but was unable to develop objective criteria on which to base those 13 decisions. Further, the wide variation in water suppliers’ existing device types and 14 conditions also made it difficult to develop a simple statistical formula and associated 15 directions that would work well in all cases. Finally, the proposed regulation provides the 16 option for in-field testing or field inspection (see below), so an overly prescriptive 17 requirement for sampling design and sample size would simply discourage suppliers from 18 doing field sampling at all.

19 Rather than prescribe a statistical formula that suppliers must use to determine the number 20 of devices for in-field testing, the proposed regulation incorporates a combination of the first 21 and second approaches. It recommends that “the sample size be no less than 10% of 22 existing devices, with a minimum of 5, and not to exceed 100 individual devices for any 23 particular device type. Alternatively, the supplier may develop its own sampling plan 24 using an accepted statistical methodology.”

25 Field inspection and analysis. This method requires the visual and, if warranted, 26 mechanical, inspection of every measurement device. Unlike the field testing option, this 27 method would not involve the use of another device to test the existing measurement 28 device. The proposed regulation requires that such inspections must satisfy best 29 professional practices. DWR staff and ASC anticipate that this would require a trained 30 individual to inspect each device and perform a basic set of tasks, such as (1) checking for 31 worn or broken elements, debris, sediment, or other factors adversely affecting the function 32 of the measurement device, 33 (2) identifying that all necessary elements are present to enable measurement (e.g. stilling 34 well(s) or other components are in place to allow measurement of any variation in water 35 level needed to calculate flow rate), and (3) testing functionality (e.g. do control structures 36 open and close freely, are gages legible, etc.). 37 38 Though this option requires that an individual inspect every measurement device, it is 39 anticipated that the time to perform the field inspection on a device would be significantly 40 less than necessary to perform in-field testing of measurement accuracy, allowing many 41 devices to be inspected in the time it would take to perform an in-field test on one device.

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1 5.2.3 Considerations and requirements for using lateral-level measurement 2DWR staff and the ASC discussed varying circumstances that could cause an agricultural water 3supplier to have difficulty in complying with the accuracy standards at a customer’s delivery 4point. Ultimately, DWR staff determined that two potential conditions could present 5circumstances acceptable for the use of a measurement device upstream of delivery points of 6multiple customers. These are:

7 Legal access. In some circumstances, the agricultural water supplier cannot access the 8 customer’s delivery point because that delivery point is on private property and no 9 easement is provided to the supplier. Although the supplier would have a contractual 10 relationship with each of the individual water users receiving delivery, the lack of legal 11 access means the supplier cannot operate, monitor, or maintain a measurement device at the 12 customer delivery point. Because the circumstances around the State vary with regard to 13 the effort put forth by agricultural water suppliers to obtain access in these situations, DWR 14 staff felt it would be appropriate to require suppliers to self-certify to DWR that they have 15 sought but have been denied access from their customers. Staff believed that requiring all 16 suppliers to obtain legal access, even through adversarial legal proceedings if necessary, 17 was beyond DWR’s authority in implementing the legislation.

18 Unique field conditions. This condition addresses the fact that some suppliers’ 19 delivery systems and some crop irrigation methods present significant obstacles to accurate 20 delivery measurement, and no measurement device is commercially available. Example 21 field conditions include locations where the differential in water level between the delivery 22 canal and the customer’s irrigation system is very minimal or where crop irrigation 23 requirements dictate large fluctuations in the delivery flow rate during a season (e.g. with 24 rice cultivation, which entails rapid flood-up prior to planting, followed by minimal 25 maintenance flows during the growing season).

26 To accommodate the potential that a device becomes available such that this condition is no 27 longer applicable, DWR staff felt it was appropriate to have DWR periodically monitor the 28 availability of measurement device technologies and report to the Legislature and the 29 California Water Commission as to when such devices may reasonably become available. 30 Furthermore, DWR staff felt that agricultural water suppliers should plan to incorporate 31 these devices at the customer location should they become commercially available. 325.2.4 Timeline and protocols for assessing, replacing, or modifying existing 33devices 34DWR staff and the ASC considered how rapidly and intensively suppliers must proceed to 35assure that all existing measurement devices meet the proposed numerical accuracy standards. 36Many members of ASC expressed concerned that the date of July 1, 2012 was insufficient time 37to assess and potentially replace many thousands of measurement devices. They explained that 38water suppliers are mostly public agencies that must provide water service to customers and 39follow existing laws and procedures when undertaking capital improvements. Their concerns 40included the following:

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1  Assessments of existing devices are labor-intensive. Suppliers have limited staff to 2 perform the added requirement, so they must add staff or hire contractors, both of 3 which take time.

4  Large new capital expenditures to repair or replace devices will require financing, and 5 public agencies generally issue bonds for such purposes. This is a lengthy process that 6 includes staff work, bond feasibility study, underwriting, rating, marketing, and sale of 7 the bonds.

8  Costs of compliance, including capital expenditures, will require suppliers to raise 9 assessments or water rates. Many suppliers expect to put the increases to a vote as 10 needed to comply with State Constitutional requirements (Proposition 218).

11  Implementation includes planning, engineering, and construction. Irrigation water 12 suppliers must provide reliable service during the crop growing season, so any system 13 downtime associated with construction must be scheduled at other times of the year and 14 when weather permits.

15 These considerations imply that some suppliers simply may not be able to bring all 16 existing devices up to the numerical accuracy standard by July of 2012. The proposed 17 regulation does however provide an option for an agricultural water supplier who is 18 unable to bring into compliance an existing measurement device before submitting its 19 Agricultural Water Management Plan by providing in its plan, a schedule, budget and 20 finance plan for taking corrective action in three years or less.

21 6.0 References

22CALFED, 2003. Final Report of the Independent Panel on Appropriate Agricultural Water 23 Measurement. California Bay-Delta Authority, Sacramento, CA.

24U.S. Bureau of Reclamation. 2008. Conservation and Efficiency Criteria. Mid-Pacific Region. 25 Sacramento, CA. 26

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1Attachment 1 – Glossary 2 3The following definitions apply to this Discussion Paper. They define words and phrases that 4DWR used in developing and describing measurement options and requirements. Words and 5phrases that are already defined within legislation are noted as such in the Reference column. 6Definitions not specifically drawn from legislation were proposed by DWR staff for purposes of 7clarifying the concepts used to develop the proposed regulation. 8

Term Definition Reference Accuracy The measured volume relative to the actual volume, expressed as a percent. The percent shall be calculated as 100 x (measured value – actual value) / actual value, where “measured value” is the value indicated by the device or determined through calculations using a measured value by the device, such as flow rate, combined with a duration of flow, and “actual value” is the value as determined through laboratory, design or field testing protocols using best professional practices. Accuracy The specific measurement requirement stated in the Standard adopted regulation, including the numerical value of measurement accuracy. Aggregated Information reflecting the total volume of water an CWC §531(a) farm-gate agricultural water supplier provides to its customers, (AB1404) delivery data calculated by totaling its deliveries to individual customers. Agricultural An agricultural water management plan prepared pursuant CWC §10811 water to SB X7-7, Part 2.8. Agricultural Water Management (SB X7-7) management Planning. plan Agricultural A water supplier, either publicly or privately owned, that CWC §10608.12. water supplier provides water to 10,000 or more irrigated acres, excluding (a) acres that receive only recycled water. "Agricultural water (SB X7-7) (SB X7-7) supplier" includes a supplier or contractor for water, regardless of the basis of right that distributes or sells water for ultimate resale to customers. "Agricultural water supplier" does not include the Department of Water Resources. Agricultural A supplier either publicly or privately owned, supplying CWC §531(b) water supplier 2,000 acre-feet or more of surface water annually for (AB1404) agricultural purposes or serving 2,000 or more acres of (AB 1404) agricultural land. An agricultural water supplier includes a supplier or contractor for water, regardless of the basis of right, which distributes or sells water for ultimate resale to customers. Approved by an A California-registered Professional Engineer has reviewed, engineer signed and stamped the plans, design, testing, inspection, and/or documentation report for a measurement device as described in this article.

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Term Definition Reference Best available Technologies at the highest technically practical level, using CWC §5100(a) technologies flow totaling devices, and if necessary, data loggers and (AB1404) telemetry. Best Practices attaining and maintaining accuracy of CWC §531(d) professional measurement and reporting devices and methods. For the (AB1404) proposed regulation, the practices are described within, practices such as operation and maintenance procedures and practices recommended by measurement device manufacturers, designers, and industry professionals. Community ditch A lateral canal used for delivery of irrigation water that is not owned nor controlled by the agricultural water supplier. Customer The purchaser of water from an agricultural water supplier who has a contractual arrangement with the agricultural water supplier for the service of conveying water to the customer delivery point. Delivery point The location at which the agricultural water supplier transfers control of delivered water to a customer or group of customers. In most instances, the transfer of control occurs at the farm-gate, which is therefore, a delivery point. Device rating Measurement devices may be rated for accuracy. Rating may be done by the manufacturer, by an independent testing laboratory, or by the field personnel after installation. If the manufacturer uses an independent testing laboratory, the measurement and reporting of the rating will be standardized and comparable across devices. Accuracy of a device typically depends on operating conditions, so the rating may be expressed as a schedule or equation related to flow rate, head difference, or other important factor affecting the device’s accuracy. Diversion Water taken by gravity or pumping from a surface stream or CWC §5100(c) subterranean stream flowing through a known and definite (AB1404) channel, or other body of surface water, into a canal, pipeline, or other conduit, including impoundment of water in a reservoir. Existing A measurement device that was installed prior to the measurement effective date of the proposed regulation. device Farm-gate The point at which water is delivered from the agricultural CWC §531(f) water supplier’s distribution system to each of its (AB1404) customers. Defined in Water Code §531(f). In-house built A measurement device that is manufactured by an device agricultural water supplier or by others to specifications provided by an agricultural water supplier. Irrigated acres For purposes of applicability of the proposed regulation, irrigated acres are calculated as the average of previous five-year acreage within the agricultural water supplier’s service area that has received irrigation water from the agricultural water supplier.

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Term Definition Reference Irrigation return The portion of applied irrigation water that is not stored in flow the crop root zone or does not evaporate from the field, Irrigation return flow includes surface return to surface water bodies such as drainage ditches, ponds, and streams. It also includes flow of applied water to groundwater. Lateral A ditch, canal, or pipeline that delivers irrigation water directly to one or more farm-gates. Manufactured A device that is manufactured by a commercial enterprise, device often under exclusive legal rights of the manufacturer, for direct off-the-shelf purchase and installation. Such devices are capable of directly measuring flow rate, velocity, or accumulating the volume of water delivered, without the need for additional components that are built on-site or in- house. Measurement A device by which an agricultural water supplier determines device the numeric value of flow rate, velocity or volume of the water passing a designated delivery point. A measurement device may include manufactured device, on-site built device or in-house built device. New or A measurement device installed after the effective date of replacement the proposed regulation. measurement device On-site built A measurement device that is built in-situ on a water devices conveyance system and may include manufactured devices or in-house built devices as components. Recycled water Water that, as a result of treatment of waste, is suitable for CWC §13050 a direct beneficial use or a controlled use that would not otherwise occur, and is therefore considered a valuable resource. Defined in subdivision (n) of §13050 of the Water Code. Retail water Any agricultural water supplier that sells water directly to supplier customers for irrigation or other agricultural use. Type of device A category of measurement devices, all of which are manufactured or built to perform similar functions. For example, rectangular, v-notch, and broad crested weirs are one type of device. Similarly, all submerged orifice gates are considered one type of device. Volumetric A revenue mechanism by which a water supplier recovers pricing at least part of its total operations cost by charging customers based on volume of water actually delivered. The volumetric charge must be based on measured volume of water delivered or on an estimate of volume delivered. The estimate must be sufficiently similar to the customer’s actual water use pattern and must be able to account for observed changes in flow rate and duration of delivery.

Water The efficient management of water resources for beneficial CWC §10817

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Term Definition Reference conservation uses, preventing waste, or accomplishing additional (SB X7-7) benefits with the same amount of water. Wholesale water Any agricultural water supplier that sells water to at least supplier one other agricultural water supplier under a permanent or long-term contractual relationship. A wholesale water supplier may also act as a retail supplier to some of its customers. Canal operating authorities and other entities that convey or distribute water to other agricultural water suppliers are considered wholesale water suppliers. 1 2 3

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1Attachment 2 – Examples of 2Measurement Standards 3

4USBR’s Mid-Pacific Region has developed accuracy standards for measurement of water 5delivered by agricultural water suppliers to customers. Its 2008 Conservation and Efficiency 6Criteria (USBR, 2008) state that agricultural contractors must implement (or show a plan for 7implementing) certain BMPs, including one for measurement of water delivered to each 8customer. 9 Agricultural contractors must “measure flows with devices that are operated and maintained to a 10 reasonable degree of accuracy, under most conditions, to +/- 6 percent by volume.”

11 The Water Conservation Criteria provide categories of measurement devices and provide examples of 12 devices in each category. USBR does not specify particular devices that must be used or that it 13 presumes will satisfy the accuracy standard.

14Other States. The following information is from Appendix C of the Final Report of the 15Independent Panel on Appropriate Measurement of Agricultural Water Use (CALFED, 2003).

16The State of Arizona requires that water suppliers or other responsible parties that are subject 17to its measurement regulations must measure irrigation water delivered. Approved measuring 18devices must be installed as close as possible to the wellhead or point of delivery which the 19device is intended to measure.

20 Entities required to measure must use a device that meets an accuracy standard of +/-10%.

21 At one time, Arizona maintained a list of approved devices that met the standard, but changes in 22 technology, requests for additions to or deletions from the list, and other factors led it to abandon an 23 “approved” list as too burdensome.

24The State of Oregon may require measurement of delivery as a condition of some water rights 25permits. There appears to be no universal accuracy standard for such permit restrictions. 26However, governmental entities are required to measure and report diversions of water.

27 Governmental entities in Oregon must measure to an accuracy of +/- 15%. No specific measurement 28 devices are required or pre-approved.

29The State of Washington has adopted a regulation (Washington Administrative Code Chapter 30173-173) for measuring diversions from surface water and groundwater. The measurement 31requirement “is not intended to apply to customers of a municipality or public water supply 32system or members of an irrigation district or similar secondary users.”

33 The combined measuring device and data recording system must measure to an accuracy of +/- 10%.

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1 Washington’s regulation allows for a range of devices, and identifies the USBR Water Measurement 2 Manual (2001) and manufacturers’ ratings as reference information for determining accuracy of 3 measurement devices.

2 20 3JUNE 13, 2011 1 1Attachment 3 – Accuracy of Existing Agricultural Water 2Measuring Devices

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